Aircraft flight control optical indicating device



Aug. 3, 1954 c. J. CRANE 2,685,226

AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE Filed July 10. 1950 5 Sheets-Sheet l THOUSAND HUNDRED INVENTOR.

CARL d. CRANE ATTORNEYS.

3, 1954 c. J. CRANE 2,685,226

AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE Filed July 10, 1950 5 Sheets-Sheet 2 M/ M 3 c I fi F /3 g I 90 H 5 lnll 5 f E I 3 HI I I mo HI //5 n f I Wm a? f0 75 4 43 4: J 4\ INVENTOR.

CARL J. CRA

/ ATTORNEYS.

C. J. CRANE Aug. 3, 1954 AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE 3 .T, a a RR m 2/ z 6 S I ma LR .t a 8 w WI. 5 a n o I 4 B H Aw 4 I fl w I K F 6 2 n n .0 I 1 1 I M I W x w a 7 1 f i a W m .v f 1 ..1 W m W 2 I I. w v m m 4 0 F l F I. y e o on M am E J m2 i d M shw I. wmxw an 2 e NO N LI a w #6 J Emma .5050 snail can INVENTOR. CARL 2 CRANE M,

ATTORNEYS.

3, 1954 c. J. CRANE 2,685,226-

AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE Filed July 10, 1950 5 Sheets-Sheet 4 Mill DIREiTION HOR ZON TRIM LAMPS DIRECT. "0W1. ALT.

07"? ,2 INVENTOR.

CARL J. CR NE LZ g; 44%.; @J

ATTORNEYS.

C. J. CRANE Aug. 3, 1954 AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE 5 Sheets-Sheet 5 INVENTOR.

CARL J. CRANE ATTORNEYS.

Filed July 10, 1950 Patented Aug. 3, 1954 QFFHCE AIRCRAFT FLIGHT CONTROL OPTICAL INDICATING DEVICE Carl J. Crane, Sacramento, Calif.

Application July 10, 1950, Serial No. 172,831

"1 Claims. 1

This invention relates generally to a unitary device for visual reference by the pilot in the control of an aircraft under blind night conditions. Generally it relates to a device of this kind in which are embodied the indicating elements required to enable the pilot to control the aircraft in relation to terrestrial objects as well as radiated electronic space patterns simultaneously and efiiciently.

It is well known that aircraft are maneuvered under conditions of blind night with respect to airborne instruments which indicate an artificial terrestrial horizon, an azimuth reference and indicating speed devices.

So far as is known no device has been made available by which the pilot of an aircraft can roll or pitch or turn the aircraft with visual reference to indicia responsive to electronic patterns which present a similar visual reference to that provided in artificial means commonly known as artificial horizons, directional gyros and the like. Neither is it known that there exists in the art a unitary indicating means which presents both an artificial terrestrial and an artificial electronic horizon each substantially indicated parallel to each other by which the craft can be maneuvered in order to satisfy spatial orientation as well as space pattern electronic orientation in a manner conventionally understandable to the pilot, who viewing the unitary indicator can take advantage of trained reflexes to safely and accurately control his craft.

In the type of night instruments using an electron beam traced upon a fluorescent screen of a cathode ray tube there is no unitary indicating reference which approximates the normal natural visual flight stimulus viewed in clear weather, and neither do such instruments provide like artificial indicia by which visual reference thereto can reconstruct on the part of the pilot an electronically radiated space pattern, both horizontal and vertical.

Various attempts have been made in the past to accomplish the result of controlling an aircraft with respect to the earth and to electronically radiated space patterns. These attempts have resulted in separated reference indicia having no visual resemblance to objective reality nor indeed if combined into a unitary indicator did the resultant present a visual reference to which the pilot could react in a normal manner with the speed required for safe and accurate flight control in the normal clear weather manner in which he was trained to fly.

The present invention therefore provides a unitary indicator natural in its presentation by which the experienced and inexperienced pilot may control his craft with respect to terrestrial and electronic planes of references. t not only provides in a unitary indicator information of bank, pitch, turn, heading deviation from electronic glide path, deviation from vertical electronic course path and rates of approach thereto, and rates of departure therefrom, but, presents this information in a normal highly interpretable and natural manner.

It is therefore a primary object of this invention to provide novel instrumental means to accomplish craft control in relation to electronic and terrestrial reference data.

Another object is to present the instrumental data for visual reference in a'unitary and natural manner.

Another object is to provide instrumental means for selecting out or selecting in those visual reference indicia instantly desired by the pilot.

Another object of this invention is to provide a means of approach to an electronically radiated space pattern for control of the aircraft in a manner which will prevent or reduce the hunting or over-controlling of the craft in the space adjustment of its flight path to that of the electronically radiated path.

A further object of this invention is the combination use of the artificial horizon established by a gyroscope having a vertical spin axis, and the presentation of the "card of a compass, gyrocontrolled compass, or directional gyro, to portray a unitary replica of the natural instrument, seen in its visual mainfestations of turning, banking, climbing and gliding.

Another object of the invention is the simple means of optically selecting various elements or indicia to be included in the unitary portrayal of needed indicia depending on the particular flight problem confronting the pilot.

still another object of the invention is the means for optically associating turn rate and heading of the aircraft with the bank angle of the aircraft to provide the all-important concept of coordination of control with feel thereby giving the pilot a freedom from vertigo and leans.

Another feature of the unitary instrumental presentation of indicia responsive to electronic glide path and course path is the manner of portraying the banking and pitching attitude of the aircraft index with respect to these two paths.

Another improved feature of the device is the manner in which the portrayed electronic horizon may be used alone as a reference for flight spatial and electronic spatial reference and then used in conjunction with the artificial terrestrial horizon to justify the flight path of the airplane along a glide beam, with the pitch attitude of the aircraft.

Another novel feature of the arrangement of combined indicia is the presentation in the same field of view, and in the same plane of reference the numerical value of landing air speed and a sky pattern.

Another feature of the portrayal of related and combined indicia into a unitary indicator for flight control and electronic navigation control is the pleasant normal natural indicating face in which the cloud pattern and horizon can appear slightly beyond the airplane index as is normal to clear-weather flight relieving the pilot of eye strain common to cathode ray type of reference 7 indicators which need frequent adjustment for brilliance control and flicker control.

A further object of this invention is the provision of an improved arrangement of aircraft instruments which have been modified so as to adapt themelves in an improved optical system wherein by simple reflection means the functional visual stimuli designated in naturally viewed clear weather manner portrays the flight attitude and rate changes of the aircraft.

Other objects and advantages of this invention will be apparent during the course of the following detailed description.

In the accompanying drawings, forming a part of this specification, and wherein similar reference characters designate corresponding parts throughout the several views,

Figure l is a display of front elevation of the indicating face of the unitary flight control indicia consisting of all optically associated elements of the instrument.

Figure 2 is a fragmentary front elevation showing various instruments of the improved craft control device, the view being taken substantially on the line 22 of Figiu'e 3, but with a shield removed.

Figure 3 is a fragmentary plan showing certain instruments of the improved craft indicating system.

Figures 4 and 5 are vertical cross sectional views taken through the instrument substantially on the respective lines 44 and 5-5 shown in Fi ure 3.

Figure 6 is a fragmentary perspective view, partly diagrammatic, showing an improved type of flight gauge known as an electronic space instrument.

Figure 7 is an elevational view of the gyrohorizon looking at the index end thereof showing the casing base in cross section and the screen in dot and dash lines.

Figure 8 is a view taken in front of the shield which blocks the instrument shown in Figure 2, and showing the indicia visible through the openings in that shield.

Figure 9 is a fragmentary perspective view showing an instrument lamp, several of which are employed in the device in connection with the optical system and instrument display indicia.

Figur 10 is a front view of the panel of the instrument.

Figure 11 is an enlarged cross sectional view taken through the altimeter control resetting means, the view being taken substantially on the line ll-ll of Figure 10.

Figure 12 is a diagrammatic view showing electric illuminating means for the instrument.

Figure 13 is a direct front view of improved display indicia for the directional gyro.

Figure 14 is a fragmentary view, partly in section, showing a horizon turn knob arrangement for raising and lowering a horizon bar of the gyro horizon instrument.

Figure 15 is a cross sectional view taken substantially on the line |5-l5 of Figure 14.

Figure 16 is a cross sectional view taken substantially on the line liii6 of Figure 14.

Figure l! is a perspective view of an optical mirror associated with the instrument.

Figur 18 is a fragmentary View showing the ivot mounting of one of the optical mirrors.

In the drawings, wherein for the purpose of illustration is shown only a preferred embodiment of the invention, the letter A may generally designat the flight instrument. It includes a casing structure B having associated therewith an altimeter C; air speed indicator D; rate of climb instrument E; directional gyro F; gyrohorizon G and an electronic space instrument H. Optical means K is provided to optically blend or merg the various indicia from these instruments at the reference plane or locus of the indicating face of the electronic space instrument H. viewed through an eye piece L. Improved illuminating means M is provided, and a shield mechanism N is associated within the instrument to perfect the display of the various indicia of the instruments, as will b subsequently mentioned.

The casing structure B preferably includes a base 2% having a panel 2i upon which the eye piece L is positioned. The casing structure furthermor includes a top wall 22, side walls 23 and 2d and a rear wall 25. The walls 22-25 may be of metal, plastic or other material. Freferably they are integral and detachably connected to the base and the front panel, as shown.

The eye piece or viewing tube L has a tapered passageway therethrough and it is directed so as to permit viewing therethrough a blended assemblage of various instrument indicia, both direct and as reflected by means of an optical system.

In the compartment of the casing is located an altimeter C air speed instrument D; rate of climb instrument E and the electronic space instrument H. The air speed and rate of climb instruments are respectively supported on the base it by means of brackets 2i and 23. The electronic space instrument H is directly secured to the base 28, and a bracket 38 secured therewith, as shown in Figure 4, mounts the altimeter C in position.

Forming part of the shield assemblage N is a shield panel 3%, shown in Figure 3, located forwardly of the instruments C, D, E, and H, which is provided with openings 32, 33, 34 and 35 therein for the respective instruments C, D, E and H, as shown in Figure 8. These instruments are located in such relation that the markings thereof are clearly visibl to an observer looking through th eye piece L.

The altimeter C is somewhat different from the conventional altimeter construction in that the casing cylindrical wall 35, as shown in Figure 2, is provided with sight opening 3'1 through which is visible the rotatable barometric dial readings 33. The latter are located peripherally upon a dial or card which takes the place of the pressure actuated pointer of the conventional altimeter and is therefor rotatable. The instrument is provided with the usual adjusting means to calibrate the instrument for varying atmospheric conditions. The adjusting means includes a beveled gear 39, shown in Figures 2, 3 and 4 of the drawings, which meshes with the manual adjusting control gear 40. The latter has a horizontally disposed shaft il extending through the panel 2! where it is provided with a manually controlled knob 42, as shown in Figure 11. The panel 2| is provided with a wheel 43 in mesh with a pinion 43 keyed upon the shaft 4|, as shown in Figure 11, and a shield 45 is provided, having a window opening to see the readings on the wheel 43, as shown in Figure 10. The shield 3| may be provided with a white index marking 50 thereon in complementary relation to the altimeter readings 38 of the dial, as shown in Figure 8.

The air speed indicator D is mainly conventional in construction including a casing 5| of cylindrical formation having a window opening 52 in the periphery of the casing, as shown in Figure 2. In place of the pointer of the conventional air speed instrument moving over a stationary dial or card, the card 53 of the present instrument is connected to the conventional pointer shaft 5 3, and the flanged periphery of the card 53 is provided with the air speed markings 56 thereon, as shown in Figure 2. The shield 31 is provided with fixed white indicating marks 55 to facilitate reading of the dial air speed marks 58.

The rate of climb instrument E, is similar to that of the air speed indicator D, has a casing structure 6E provided with a segmental peripheral opening 6! in the cylindrical end thereof through which are readable the markings 62 upon a peripheral flange of movable dial or card 63. The dial is keyed to the pointer shaft of the conventional instrument. The readings 62 are visible through the shield opening 34 of Figure 8, and said shield has white reference markings 65 for determining the proper reading.

The artificial horizon G is basically of the Sperry type, but modified as hereinafter mentioned. In includes a casing structure 10 mounted upon the front panel base of the instrument A. The visible opening of the gyro horizon does not face the pilot, but faces the direction of flight. In place of the conventional movable horizon bar the instrument G is provided with an airplane index 13, shown in Figure '2 of the drawings and elsewhere. The index 13 has a nose simulation portion l3 located within a v-shaped central portion 13 The ends of the latter have aligning wings 13 and angled tip 13, the outer surfaces of which are at an angle of 45 to the wings 13. In a 30 left bank the left wing root of the V portion 13 will be parallel to the horizontal as shown in the drawings; in a 45 left bank the left wing tip 13 would be perpendicular to the horizon, and in a 60 left bank the right wing root of the V portion 53 would be perpendicular to the horizon. The index 73 functions the same as the horizon bar of the conventional gyro-horizon instrument. A conventional caging adjustment is provided of the knob and gearing type shown at 15 of- Figure 3. The gyro-horizon instrument G has a white colored'horizontal bar l7, and means for manually raising and lowering it. In the conventional gyro-horizon the airplane index is manually moved upward or downward by means of a trim mechanism, whereas in the present invention the white horizontal bar l? is so raised and lowered. In the conventional instrument the horizontal bar 6 is operated by the gyroscopic mechanism, but in the present instrument the airplane index shown at 13 is so operated. The horizon H is the terrestrial horizon and the index 13 is the bank and climb index, as will be subsequently mentioned.

Referring to Figures 3, 14 and 15, the white horizontal bar 11 is mounted upon the upper end of a vertically disposed shaft 18 sliding in a bearing 19. The shaft is spring loaded at to normally force the flanged end 8| of the shaft against a cam 82. The latter is rotatably mounted upon a shaft 83. The latter has a gear 84 in mesh with a gearing and trim knob control assemblage indicated at 85 leading to the face of panel 2|. The terrestrial horizon reference marks H are etched on the cover glass 17 of instrument, as are also a vertical line 11, a horizontal line 77 a center circle H and concentric arcs H Referring to the direction gyro F, the same includes a casing 9i with its axis normal to the axis of the instrument G. It is supported upon the frame of the casing B, 'adjacent to the side wall 23.

The directional gyro F is substantially equivalent to the conventional Sperry directional gyro except that its card 9|, as indicated in Figure 13 of the drawings, is provided with a cloud pattern 92 and degree indicia. The latter are reversed, since they will be reflected from an optical mirror, as will be subsequently described. This instrument may be replaced by other directional indicating devices, such as the repeater card of well known and conventional gyrosyn or fluzgate compass repeaters, if so desired.

The cloud pattern can be tinted in contrasting colors. For instance clouds in the North quadrant can be tinted white; in the East blue; in the South amber and in the West red. This will associate cardinal directions with the cloud line.

As part of the shielding assemblage N, a second shield 94 is provided, as shown in Figures 3 and 13 of the drawings. It has an opening 9'5 therein through which are visible the cloud pattern 92 and the indicia 93, with reference to a white indicator mark 96, which may be located upon the shield 94. The dot and dash lines in Figure 5 show the opening in this shield.

A third shield 91 is shown in Figure 3, within the casing B in front of the instrument G. It has an opening indicated by the dot and dash line 98 in Figures 5 and 7, thru which are visible the terrestrial horizon Ti and the airplane index 73.

The gyro horizon G and directional gyro F are provided with the usual operating suction to the cases thru the conduits Hill and IM as shown in Figure 3. Air withdrawn from the cases is replaced with air that enters thru any suitable openings (not shown) to the cases.

The air speed meter D is provided with two tubes i BI and H32, the former leading to the pressure element, at the Pitot-static tube, and the other leading to the static element of the Pitotstatic tube. The static line is connected to the cases of the air speed meter, altimeter and vertical speed indicator and functions as in conventional practice.

Referring to the optical image concentrating means K, the same includes partial mirrors H and 87. That is, they are both transparent, partially surfaced mirrors and are disposed vertically with their faces substantially to each other. The mirror H is fixed, but mirror '81 has adjusting means which will be subsequently described.

It is understood in the art that a partial mirror is one that has a chromium or alumium deposit on the front or the glass rather than the back. The intensity or amount of the deposit will determine the amount of light transmitted thru the mirror in relation to the amount reflected. Since the reflecting agent is on the front of the glass only, one image is reflected.

The mirror H races diagonally at an angle of 45 with respect to the indicia reading of faces of instruments and G. The mirror 8? faces the opening of tube L at angle of 45. The rn'rror 8! reflects the card of the directional gyro to the observer. The airplane index and horizon of the instrument G, are viewed thru two reflections, one from the first surface of the mirror l! and again from the first surface of the mirror 3?, to the eye of the observer. These images or the two instruments F and G are thus reflected substantially as shown in Figure 5, where the dot and dash lines designate the reflection from the instrument G; the card of the instrument F being clearly visible thru the n.irror ii. The broken border dot and dash lines in this view designate the shield 94.

The readings from the instruments C, D, E and H are visible thru the mirror 8?, without reflection.

The mirror ii is preferably mounted in suitable channel moulding llil shown in Figure 3 of the drawings, upon the base all of the casing structure.

The mirror 3? is mounted as shown in Figures 3, 1'7 and 18, in order that it can be adjusted. As shown, the mirror 3'! is mounted in suitable moulding Ht, channeled at the bottom margin thereof. The moulding ill) is preferably pro vided with suitable extensions ill, which have hinge barrels adapted to align with complement-- ary hinge barrels of leaves H2 screwed or otherwise detachably mounted upon the base it of the casing structure. These hinge barrels receive pintles H3.

The means for manually controlling the position of the mirror Bl includes a still but flexible spring steel wire H5 rotatably bearing at H6 in a bracket ill attached to the mirror 8?. The wire H5 at the panel 2% is provided with screw threads lit threaded in a suitable opening in the panel 2 i. The wire is controlled by means of a knob H311 thru feeding the wire in or out the mirror may be caused to tilt to the desired degree in order to properly transmit the image to the eye of the observer.

Referring to the illuminating means M (Figures 3 and 12) the same includes lamps 56 and 355i for casting rays of light upon the indicia of the instruments C, D, E and H; a lamp N52 for casting rays of light upon the indicia of the instrument F, and a lamp 553 to cast rays of light upon instrument G.

The type of lamp is shown in Figure 9. it includes a Plexiglas tube 155 externally of dull black color, and provided with a slot its therein thru which light rays are transmitted. A lamp bulb i5? is supported by the usual socket mechanism I 53.

As shown in Figure 12 of the drawings the lamps are connected in a circuit 25in. The lamps use and 55! are provided with rheostat switch 158a for the control thereof, and the lamps I52 and i523 respectively have individual rheostat switches 55% and I60. The knobs for control of 8 the switches ISM, I59 and Hill are shown upon the panel 2! at i582), [59a and [60a respectively.

All of the shields 3i, e l and 9"! of the shielding means N are provided with dull black surfacin particularly the sides facing the optical arrangement, in order to expose to view only the scales and indicia, and to kill all unwanted refiections and exposed parts.

It should be noted that the density or the two partial mirrors is such that there is a pleasing balance or readability between the various images. This is also controlled by the amount of illumination which is cast upon the indices of the various instruments. The intensity of illumination will be regulated by the rheostat switches to suit night or day conditions. The distances from the eye of the observer to the various indicia of the instrument, however reflected, or illuminated, must be substantially the same in order that the superimposing oi the various instrument indications will provide an absence of parallax. This principle may be departed from slightly in order to give an impression of depth when receiving the reflected images, such as may be desired in having the image of the face of the directional card, upon which the cloud pattern is portrayed, a slightly greater distance away; giving the efiect of a cloud pattern line beyond the airplane index of the artificial hor'mon instrument. Such slightly greater distance will not result in parallax of any order that would be detrimental to the precise use of the instrument.

Referring to the electronic space indicator H, as shown in the various views of the drawings, and in fragmentary and diagrammatic form in Figure 6 of the drawings, the instrument includes a casing structure 528 which supports a cover glass 62% at the front thereof, held in the case by means of clips 22. A shield i223, which is spherically curved and segmental in cross section, is supported by brackets ifi l. The convex face is colored dull blacl: and over it operate the electronic vertical bar i25 and electronic horizontal bar M26.

The casing structure lZil supports galvanometers l2? and I28 in any approved manner. The vertical bar 525 is connected by an arm [25 to the movable coil of galvanometer [21. The bar or pointer E28 sweeps up and down and is connected by an arm E28 to the movable coil of galvanometer {23. The arrows shown in Fig. 6 at the face of the instrument designate the sweep of the bars 1'25 and iZE.

The galvanometers lill and 28 are essentially microammeter types, the coils thereof rotating to swing the pointers either left or right or up and down, depending on the flow direction of current. Of course the pointer I25 only swings left and ri ht and the pointer 128 up and down. The galvanometers are actuated by means of energy received from associated radio-receiving equipment and be the well known HIS localizer beam, the energy received from an Omni-Range receiver; the energy received from a Directional Finder Receiver, or that received from a Sperry Zero-Reader.

The vertical electronic actuated bar or pointer 255 is provided with laterally extending horizontal arms see, the ends of which are downturned, and the general appearance of which is that of a silhouetted perspective view of an approaching runway head-on. Complementary thereto, the electronic horizon bar l26 is provided with a horizontal arm portion it! supported below the bar I26 by a bracket H2. The arm [3| is intended to present the leading edge view of the runway.

The vertical bar I25 and the arm positions I30 are tinted green upon their visible faces. Likewise, the complementary segment or arm portion I3I may be tinted green. The face of the arm I26 may be tinted some contrasting color, if desired.

The horizontally disposed up and down swinging arm or pointer I26 registers movement up when the'aircraft is below the glide beam and down when the aircraft is above the glide beam. The vertical arm or pointer I25 represents the movement of the plane to the right or left, of the ILS localizer beam, or the Omni- Range course, or indicates the transmitted signal outputs from the Sperry Zero Reader by selected switching.

When the cross pointers I25 and I23 are in the neutral or zero position for landing, the portions I36 and IEI will represent a closed figure.

The socket plug I33 receives the wire leads from the galvanometers I2? and I 28 as shown. The pointers I25 and i26 are transversely curved, as

indicated in Figure 6, in order that they will always remain in close proximity to each other as the pivoted pointers of the galvanometers swing, and thereby eliminating parallax, regardless of their position.

Switching means diagrammatically illustrated in Figure 6 is provided for selecting the output of the Instrument Landing System, now common VHF, installed at U. S. ports, or the output from the Omni-Directional Range, or the output of such other devices as the Sperry Zero Reader.

Figure 6 shows the Omni-Range output at I40; the ILS output at Iii and the Sperry Zero Reader output at I42. In Figure 6, I 33 represents a pivoted switch handle which, as shown diagrammatically, is connected to a switch actuating cam I44 by means of a shaft I45. The Omni-Range output is provided with a switch I46; the ILS output with a switch I47; and the Sperry Zero Reader output with a switch I48. The single cam it is intended to selectively actuate the switches I46, WI and I lB, as shown. The lines leading to the electronic vertical and horizontal actuating galvanometers I2! and I28 are shown in the drawings. It is to be noted that placing the switch arm or handle I i-3 in position for actuating the switch I i'l to the cam I4 2 will energize both pointers of the cross pointer instrument H, the runway localizer vertical pointer and the glide path horizontal pointer, as indicated. Actuating the Omni-Range switch Hit by means of the cam M l, through turning the handle I 53, will actuate the vertical pointer of the instrument H by whatever current, in microamperes, is flowing from the receiver to the cross pointer galvanometer. At this time the current to the glide path (horizontal pointer) is left open, since the Omni-Range receiver includes no glide path receiver.

The Sperry Zero Reader output M2 consists of the yaw, compass, bank and radio track unit I42, and the pitch, altitude and glide path unit I42 as is known to those skilled in the art. The unit I42 actuates the galvanometer of the cross pointer instrument controlling the vertical electronic bar, and the unit I 42 actuates the galvanometer of the electronic horizontal bar.

It is to be noted that the movable switch members of the switches I45, I 41 and I48 are spring loaded to normally opened position. They may be of any commercially available type, and are only diagrammatically shown in Figure 6. As

10 shown in the drawings, the springs are of the compressor types.

It is to be noted that resistors I 59 are provided for each of the two units of the ILS output and Sperry Zero Reader output, and a single resistor unit I i9-- for the Omni-Range output. In the open position for the switches, the switch contacts are electrically made to place the resistors across the circuits leading to the switches respectively from the outputs I45, I iI and M2. The high resistance resistors have the purpose of placing an electrical load on the output of the respective devices, in order that they may be left in a hot or stand-by condition, electrically ready for oil-switching at all desired times, even though the switch handle I43 is in an off posi tion.

With the switch handle M3 in an oil position the resistor of the switch I d6 is shunted across the two wire circuits leading to the said switch from the output I49; the resistors of the switch It? are shunted respectively across the two wire circuits leading from the localizer unit of the output MI and the two Wire circuits leading from the glide path receiver portion of the output MI, and the resistors of the switch I48 are shunted, one of them across the two wire circuits leading to the switch from the unit Hi2 and the two wire circuits leading to the switch from the unit I42 It will be apparent from the foregoing that the invention consists of a real combination of flight stimuli imparting a visual coordination or mixing of natural flight attitudes and rates. The invention does not consist of a mere projected aggregation on a screen of a plurality of instrument indicia. It is an optical combination, by a simple reflection, of functional visual stimuli, reporting simultaneously in naturally viewed clear weather manner the flight attitude and rate changes of the aircraft, with respect to terrestrial planes of reference as well as to electronic planes of reference; or to mixtures thereof.

Referring again to the gyro-horizon instrument G, the airplane index it remains parallel to the real horizon, and the horizon line I! banks with the aircraft. Thus is imparted correct knowledge of the bank angle in a manner to relieve the pilot of bank vertigo. At the same time this imparts a. banking reference to the artificial terrestrial horizon, as well as the artificial electronic horizon of the instrument H.- In Figure 1 is shown the observers view of the various indicia. It indicates to the pilot the aircraft is flying with the left wing down, and the degree is determined by the relation of the lines of the index is to the horizon and vertical lines otherwise visible. That is, if the left wing tip line assumes a position perpendicular to the horizon, a bank angle of 45 would instantly be indicated to the pilot, etc. The aircraft upon which the instrument of Figure 1 is located is in a left bank and turn, resulting in the cloud pattern of the background and its markings of azimuth moving from left to right. The speed with which this movement takes place depends upon the type and speed of the aircraft used. The pilot familiar with the type of aircraft soon learns and feels the proper bank angle for rate of turn when he can see the natural instrument in clear weather, and in the case of the present invention a similar result can be achieved. Should the aircraft begin to climb while in the left turn, the airplane index it would appear to rise above the horizon line Ti and its silhouette would then appear to be passing across the cloud pattern.

Should a diving turn to the left be started, the airplane index 13 will begin to fall, passing the horizon line l! and then assume some position below the horizon line representative of the glide angle. It is therefore quite obvious that various combinations of bank, turn, climb and glide will present to the pilot a realistic visual stimulus of the various flight attitudes and turn rates which will be presented in the normal natural manner rather than in the split unnatural present methods of indicating flight attitudes and changes.

Referring to the pilots view of the instruments as shown in Figure 1, it will be noted that the lubber line 85 is over the directional scale indicating 27-0. The airplane index shows the aircraft to be to the right of the runway course beam as represented by the electronic vertical marker H5. The airplane index 13 indicates a gliding left turn in progress, and it lies above the glide path electronic horizontal bar I26. The latter lies below the terrestrial horizon line 1?, indicating that the aircraft is above and to the right of the flight line which will bring the aircraft to a 'landing on the runway, for example, whose axis lies 270.

As the left turn progresses, the desired object would be, first, to have the nose of the airplane index intersect the electronic vertical I25 at the vertical lubber line. This then would insure that the aircraft was on the runway course beam and as this obtains, the pilot noting the direction indicator, will then turn the aircraft to the right to recover a heading of 270, insuring that the aircraft is headed down the runway axis. This condition can be met and held only in the absence of a cross wind component.

Should a cross wind be present, say from the South, some heading less than 270 will be sought. This would permit the electronic vertical 25 to pass through the nose of the airplane index '53. This procedure of adjustment, using the present invention is quite as easy as would be obtained in an approach to the runway in clear weather.

By visual flight reference, simultaneously viewing of all necessary factors, namely direction,

, rate of change of direction, displacement from runway course beam, and rate of closure thereto are seen and evaluated in a manner substantially identical with the normal natural instrument.

After reaching a steady runway course, to be held for the approach, the glide beam is approached, either by reducing the speed, maintaining attitude of level flight, and accepting a rate of descent until the electronic horizon i26 rises and intersects the terrestrial horizon 1'! in every case, at which moment the aircraft is on the proper glide path.

Another method of reaching the desired glide path is to change the pitch attitude of the airplane index i3, placing the nose on or in the direction of the glide path electronic horizon, applying or reducing engine power to maintain desired air speed, and as the electronic horizon I28 returns coincident with the terrestrial horizon 11, the pitch angle changes producing a follow-up method of pitch control of the aircraft to produce the important accurate maintenance of path justification with the glide path to the runway for landing of the aircraft.

In the approach landing just described, no other instrument need be referred to at any time other than the pilots view through the viewing tube, since all necessary elements are contained in the presentation of indioes shown in Figure 1.

Obviously if a landing is not being made, and if the cross pointer electronic vertical or electronic horizon are not needed for navigational purposes, such as would be true in flying a VHF radio range, or the Omni-Directional ranges, the light switch controlling current which illuminuates the cross pointer indicator may be opened, thereby eliminating the pattern from view. Any of the other scale or index presentations may be eliminated or selected at will. For instance, in clear weather the only desired presentation may be the cross pointer pattern in order to use the electronic vertical in conjunction with the Omni-Directional range, or other electronic navigation systems which use a leftright sensing galvanometer.

Various changes in the rearrangement of the various units of the instrument may be made within the casing structure without departing from the spirit of the invention or the scope of the claims.

I claim:

1. In a craft controlling device combina tion of a supporting frame, a gyro horizon having an index in the form of an airplane mountei to move in designation of bank, climb and dive and having a terrestrial horizon index disposed to parallel the transverse axis of the craft to which the instrument is attached, a directional gyro having an index simulating cloud pattern and turn degree indications sensed functionally, an electronic space indicator having complementary vertical electronic and horizontal electronic indioes with radio receiving energy actuated means for movement of said ver tical and horizontal indices in designation of plane movement to the right or left and up and down with respect to the localizer beam and glide beam, and reflecting an optical means blending said gyro controlled indicia and the vertical and horizontal indicia of electronic space indi cators together in normally sensed complementary relation at a, common locus in realistic visual stimulus of the various flight attitudes, turn quantities and path changes of the air craft to which attached whereby to facilitate the pilot's utilization of normal sense impressions.

2. A flight instrument as described in claim 1 wherein the vertical index of the electronic space indicator is provided with an inverted substantially U-shaped index movable with the vertical index and including a horizontal portion and appended outwardly angled portions in complementary position to cooperate with the horizontal index of the electronic space indicator in flight designation for runway landing.

3. In a craft controlling device the combination of a supporting frame, a gyro horizon having an index in the form of an airplane with a wing and mounted to move in designation of bank, climb and dive and having a terrestrial horizon index located to parallel the transverse axis of the aircraft to which the instrument is attached, said airplane index being provided with a centrally located ll-shaped body portion and the extreme wing ends being down-turned in divergent relation, a directional gyro having an index simulating a cloud pattern and turn degree indications correctly sensed, and. reflecting and optical means associated with the indicia of said gyro horizon and directional gyro blend ing all of the indicia thereof together at a common locus in realistic visual stimulus of the various attitudes and turn quantities and path 13 changes of the aircraft to facilitate the pilot's coordination of normal sense impressions.

4. A flight designating instrument for aircraft comprising an index, gyroscopic means for operating said index in designation of turn of an aircraft with movements sensed in accordance with a normal clear weather turning view as seen by a pilot from the aircraft, a second index, gyroscopic means for operating the second index in designation of bank and pitch with sensing and degrees of bank and pitch movements corresponding to those of an aircraft in flight, electronically responsive horizontal and. vertical indices, electrical means for operating said electronically responsive indices with locating movements corresponding to the position of the aircraft with respect to radiated space patterns definitive of runway location and orientation, and means for integrating all of said indices and their related movements at a common locus for stimulation of pilot responses in accordance with normal conditioned reflexes.

5. A flight instrument for aircraft as set forth in claim 4 wherein the means for integrating all of said indices comprises an optical system, and intensity adjustable illuminating means for the indices.

6. An aircraft instrument for indicating to the pilot a complete visual stimulus of the movements of the aircraft about its axes and the displacement of the aircraft from space radiated electronic patterns defining landing runway location and orientation, comprising indicating elements defining respectively the movements of the aircraft about its three axes, means for actuating said indicating elements responsive to turn, direction, pitch and bank of the aircraft, electronic actuated horizontal and vertical indices, electronic means for cooperatively actuating said horizontal and vertical indices from space radiated signals, and means for superposing the turn, direction, pitch and bank indicating elements, and electronic vertical and horizontal indices in a superposed relation all in the same field of view of a pilot for giving a complete visual stimulus of the movements of the aircraft about its three axes and with respect to runway approach.

'7. An aircraft instrument for indicating to the pilot a complete visual stimulus of the movements of the aircraft about its axes and the displacement of the aircraft from space radiated electronic patterns defining landing runway location and orientation, comprising indicating elements defining respectively the movements of the aircraft about its three axes, means for actuating said indicating elements responsive to turn, direction, pitch and bank of the aircraft and in degree, rate, direction and sensing corresponding to a pilots view during clear weather flight, electronic actuated horizontal and vertical indices, electronic means for cooperatively actuating said horizontal and vertical indices from space radiated signals, and means for superposing the turn, direction, pitch and bank indicating elements, and electronic vertical and horizontal indices in the same field of view of a pilot for givinga complete visual stimulus of the movements of the aircraft about its three axes and with respect to runway approach.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,760,163 Morris May 27, 1930 1,980,886 Talafre et al. Nov. 13, 1934 2,019,234 Nistri Oct. 29, 1935 2,137,194 Weber Nov. 15, 1938 2,178,637 Link, Jr. Nov. 7, 1939 2,283,190 Crane May 19, 1942 2,291,635 Kenyon Aug. 4, 1942 2,357,060 Robinson Aug. 29, 1944 2,458,022 Phelps Jan. 4, 1949 2,463,529 Ferrill Mar. 8, 1949 2,467,412 Wathen Apr. 19, 1949 2,531,492 Angst et a1 Nov. 28, 1950 2,531,521 Link Nov. 28, 1950 2,537,996 Hankes Jan. 16, 1951 2,557,380 Hickox June 19, 1951 

